V5 Pinking

Colin C

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Apr 1, 2003
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The air mass meter is the most probable cause for the pinking, I have come across this before on a customers car. The airmass meter does not register the amount of air going into the engine so the engine ECU does not inject enough fuel hence the pinking due to the lean mixture. Get this fixed ASAP before you cause internal engine damage !!!
 

Jester77

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Nov 1, 2008
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I've just run Vagcom and it found 3 faults, only problem is instead of saving them I cleared the codes by accident, what a fool.
Can I get them back -Help!!

First error was the Lambda sensor, becuase the codes are gone I can't remember which one.
 
Last edited:
Feb 26, 2009
5,275
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Wolverhampton
Unfortunately you can't get them back, however if they are still relevant they will return after about 100 miles of driving. By any chance is your car running like a bag of spanners now? Even worse than normal?
 

Jester77

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Unfortunately you can't get them back, however if they are still relevant they will return after about 100 miles of driving. By any chance is your car running like a bag of spanners now? Even worse than normal?

Haven't really taken the car out today so it's hard to say.
Gutted I cleared the codes though, I just hope they come back.
One of the other errors was something to do with the catalytic converter I think, I was hoping the lambda sensor problem was causing the other problems.

Anything else I can check with VagCom?
 
Feb 26, 2009
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One of the other errors was something to do with the catalytic converter I think, I was hoping the lambda sensor problem was causing the other problems.

Anything else I can check with VagCom?

It is usually the case that the actual problem generates more than one fault code. For example, a faulty MAF would generate;

MAF sensor open or short circuit
Fuel trim out of range
Lambda sensor mixture out of range
Multiple misfire detected

And yet, the only one that is actually relevant is the first one. It is also a pain that if it's the first time you've checked the fault codes, you might pick ones up from a long time ago. So if the previous owner had their MAF changed but didn't clear the codes, all of those messages would still be there.

There are various realtime parameters that you can monitor with VAGCOM, unfortunately with no knowledge of what the values should be, I can't really suggest what to look for.
 

Jester77

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Nov 1, 2008
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Fuel trim out of range was the other fault that came up, I just wish I could get the faults up again as I have a lot of motoring to do this weekend.

When I find out what sensor has gone I guess the next question I'll be asking is how to fit the thing?
 
Feb 26, 2009
5,275
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Wolverhampton
Fuel trim is controlled by the MAF, it being out of range means that your MAF signal is goosed. Get yourself down to eurocarparts or GSF, and get a replacement (usually an exchange unit). Around £75 last time I checked.

To change it, find the air filter box. Just to the left of it is the MAF. Disconnect the wire connector off the back of it, undo the circlip connecting the MAF to the pipe. Unscrew the top of the air filter box, then unbolt the MAF from the box. Reverse the process to put it back together again, and drive it like you stole it...

OK, the last bit isn't necessary, but you should find it's fixed the problem.
 

Colin C

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Apr 1, 2003
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As I had previously stated airmass meter / MAF is the 1st item you need to replace especially with the 2 fault codes you have just listed. As Slimy mentioned they are only about £75 and take only a few minutes to fit.
 

Jester77

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Nov 1, 2008
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For now I'm going to wait and see what lambda sensor I need to replace, Vagcom must be my best way to go before I spend more money as I've already brought plugs I don't need.
It says the lambda sensor measures the oxygen content in the exhaust gases, the sensor then sends signals back to the ECU to calculate the engines fuelling requirements, sounds just the ticket to me, if that fails then I'll changed the MAF.
 
Feb 26, 2009
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Wolverhampton
I don't believe the lambda sensor is at fault. As Colin originally said, all signs point to the MAF being at fault. The lambda sensor is merely complaining that the fuel mixture is wrong, it's the MAF that is causing it. The MAF has much more to do with fuel mixture.

With VAG cars, I always go with the zebra principle. If you hear hooves behind you, just go with the obvious and think horse, not zebra. With this problem, you have a part that is known to fail much more frequently than it should (MAF) and a part that is fairly reliable (lambda sensor).

I'd agree with your first thought though, get some miles done, get the fault codes back with VAGCOM then decide what to do. :)
 

Jester77

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Nov 1, 2008
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West London
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Just ran Vagcom and it's found just 1 fault this time.
1 Fault Found:
16523 - Oxygen (Lambda) Sensor B1 S2: Response too Slow
P0139 - 35-10 - - - Intermittent

Not sure what to do now as I can't afford to change things just on the hope it will work.
 
Last edited:
Feb 26, 2009
5,275
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Wolverhampton
Can someone point me to the MAF part on Euro car parts or GSF please?
Can't find it for the AQN engine.

Wow, I'd forgot just how painful the Euro car parts website is! This is the GSF entry;

187VG0060 AIR MASS METER G4/BORA AQN 2.3/AQP/AUE/BDE 2.8/BFH 3.2 57.00

As for the fault code, I tend to disregard intermittent faults. Clear it and see if it comes back.
 

AP_V5

Active Member
Jan 19, 2010
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Sussex
I had that fault 16523 - Oxygen (Lambda) Sensor B1 S2: Response too Slow

cleared it and not come back, this is common on vag engined cars as others have said more likely to be something else, also a leak in the exhaust system can cause the above fault code too.
 

Jester77

Active Member
Nov 1, 2008
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West London
www.ukdrn.co.uk
Hi All.
Done some milage in the car last weekend and got some fault codes, the engine management light was on before I went 5 miles.
I stuck some high octane in the weekend and the pinking wasn't as bad as before (down 60% at least) but it was still there, the other thing is since the refil the car now starts in the morning at the turn of the key - no gas needed.

The other things that's really annoying are the fans, they come on every 30 seconds (90.0c) and are loud compared to the old car, now I don't know if my old car had quiet fans and did the same or is this a fault.

Anyway here are the fault codes for your consideration please.
New MAF first still?

3 Faults Found:
16523 - Oxygen (Lambda) Sensor B1 S2: Response too Slow
P0139 - 35-10 - - - Intermittent
17560 - Long Term Fuel Trim Additive Air Bank 1: Range 2: System too Lean
P1152 - 35-00 - -
16804 - Catalyst System: Bank 1: Efficiency Below Threshold
P0420 - 35-00 - -

Capture2.JPG
 
Feb 26, 2009
5,275
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Wolverhampton
If I was a betting man, I would put lots of money on it being a MAF fault. As soon as the fuel trim goes out of range, that is the MAF up the swanny.

Coincidentally enough, mine is starting to pink under hard acceleration, so I'm expecting to be changing mine quite soon. I've not got any fault codes yet though.

I believe secondary air injection is only used when the car is warming up, so it won't always be active? Although I'm not sure on that one.
 

Colin C

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Apr 1, 2003
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Southampton
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The fault with the fans pulsing / noisy every 30 seconds is the low speed resistors burn't out in both cooling fans, switch your AC off and this will stop the fans pulsing. If this does stop the fans pulsing you will need a pair of cooling fans, I have the same fault on my own car :(

The secondary air system only operates on cold start for less than a minute, sounds like a vacum cleaner. As you have VAG com you should be able to final control the relay to test the secondary air system for leaks, the pipes are hard plastic approx 1 inch diameter. If there is a leak between the combi valve and air intake track it could cause a lean mixture / pinking but it's unlikely.
 
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